US2267882A - Pump piston - Google Patents

Description

Dec. 30, 1941. R/A. WILSON 2,267,832

' PUMP PISTON Original Filed Sept. 1'7, 1936 MEQ 0 7 a/ a? i D H 39 If Patented Dec. 30, 1941 Application September 17, 1936, Serial No. 101,232 Renewed June 7, 1940 7 Claims.

The invention relates to an improvement in pump pistons and particularly that type of piston which is used in a slush pump to maintain the circulation of mudin the rotary method of drilling wells.

It is one of the objects of the invention to provide a composite piston wherein the resilient packing portions thereof are retained in a position by means of a thin metal flange which is afllxed to the piston body.

Another object of the invention is to provide a composite piston which can be disassembled in order to renew the resilient packing portions thereof.

Another object of the invention is to provide a telescoping body for a slush pump piston so that the reenforcing flange is firmly clamped by the telescoping parts of the body.

Another object of the invention is to provide a curved plate portion to support the ends of the resilient packing and wherein such plates are firmly anchored to the piston body.

Still another object of the invention is to provide, in combination with a resilient sealing portion for a pump piston a supporting end plate.

Still another object of the invention is to provide a piston wherein the packing portions are slipped over the hub portions and then the hub portions clamped together.

Other and further objects of the invention will be readily apparent when the following description is consideredin connection with the accompanyin drawing, wherein:

. Fig. l is a transverse sectional view taken through an assembled piston and illustrating the 35' certain parts form of the body and plate.

It is well understood that pistons of the type herein described are employed in slush pumpscomprises the body portion 1 which is. cylindrical and body combined are of slightly less lengthv than the entire piston. Fixed to the'periphery of the end of'the body portion I is an annular end plate It which is of a suitable sheet metal so that it will resist considerable stress. This distance and then flares outwardly to provide the supporting portion 28 thereof. Any desired number of openings or recesses 2| may be provided in the plate if desired. These openings serve a dual function in that they,

2 weight and permit application of fluid pressure 40 been found to be satisfactory. The reinforcing is desired because expansion of (the resilient member should occur adjacent the corner or lip and are disposed in a cylinder for reciprocation,

the valves of the pump being such that the pis- 4 ton is double acting.

The piston is caused to reciprocate by means of a piston rod 2'which usually has a reduced snugly over the hub ll.

ring 22 and the end directly against the sealing material 22. The foregoing construction facilitates desired clamping of the sealing material on the piston and provides a piston that is both light and strong.

In assembling the piston the packing ring 22 may be slipped over the body] so that its edge will abut against the plate M. The contour of theend face 23 of the packing ring 22 is the same as the inside contour of theplate 14 so that the resilient ring will fit snugly against the plate. Fluid pressure acting upon the end plates also acts directly upon the end face 23 of the packing ring'22 through the openings 2!.

The ring 22 may be made up of any suitable material, but rubber, which is reinforced with the fabric portions 25 adjacent its inner end, has

portion 28 rather than at the heel 21 thereof.

In order to properly support the sealing ring 5 22 a rigid flange 3|] is next provided in the piston assembly. The flange is in the form of an annular plate having a recess 3! therein which fits The diameter of the flange 3!! is slightly less than the diameter of the cylinder in which the piston is to reciprocate so as to allow a slight clearance but still. serve as a support for the sealing ring 22.

The other half of the piston, insofar as the plate I! are concerned, is

ton body of metal is indicated generally at 5 and 55 identical with. the ring 22, but the end plate on right-hand end of the piston is mounted n a sleeve 35. 1 This sleeve is in the form of p having a hollow inside area 38 so that it can be-telescoped over the hub II as seen-in Fig. 1.. The outside diameter of this cap I! is the same as the diameter of the hub II. This cap ll will be of suflicient length so that its inner end I! will abut against the flange Ill.

It seems obvious that the resilient rings can be slipped'over the body] and the cap 35 and then the parts assembled as shown in Fig. 1. A

nut II or other fastening means can be afllxed to the end of the reduced portion 3 of the rod 2 and if it is tightened'upit will clamp the parts securelyinto position against the body 39 on the piston rod 2. The clamping action is imperative because the enormous pressure to which the piston is subjected in some instances causes leakage along the piston rod and destroys the parts.

with the present structure the flange 30 and the packing ring 22 are securely clamped into position between the end plates Il and then against the flange 30, the flange 30 in turn being securely will be held by the welding material IS the same as previously described.

The cap 35 and body 6 are also slightly modified in that, the body extends entirely through the piston and is reduced at 43 to form a shoulder. A complementary shoulder on the inside of the cap II is in spaced relationwith the shoulder 4! so as to give a positive clamping of flange 3.. The end of the body extending through cap II is threaded'at 44 to receive a loclrnut so that the piston may be assembled and locked together before being placed on the rod 2.

Broadly, the invention contemplates a slush pump piston in which the resilient packing portions can be readily removed and in which the number of parts which must be clamped together is maintained at a minimumand in which the reinforcing structure is rigid so as to support the packing element.

What is claimed is:

1. A slush pump piston comprising a support ing body, a reduced hub thereon, a sleeve fltted on said hub, a flange disposed about said hub and clamped between the ends of said sleeve and body, a sheet metal end plate flxed to each said body and said sleeve adjacent the outer ends thereof, said plates being recurved radially, and

2. A pump piston comprising a body member having-a flange portion and a reduced portion, a-

peripheral shoulder on said body member intermediate its ends, a flange on said reduced portion contacting said peripheral shoulder. a sleeve telescoped over said reduced portion said sleeve contacting said flange andhaving a flange portion, and asealing memberbetween the flange and each of said flange'portions, said flange portions being radially recurved convexly in. the direetion of said flange.

3. In a pump piston, body members in telescoped relation, a radially extending flange clamped therebetween, sheet metal flanges secured to the opposite ends of said assembled ,body members, said flanges being annularly dished between their peripheries and the point of attachment to the body members and a resilient sealing member interposed. between the radial flange and each of said sheet metal flanges and in abutment therewith. 4

4. In a pump piston, body members in telescoped relation, a radially extending flange clamped therebetweenand foraminated sheet metal flanges secured to the opposite ends of said assembled body members, said flanges being annularly dished between their peripheries and the point of attachment to the body members.

5. A pump piston comprising a body, a reduced area thereon, a flange slipped onto said reduced area, a'second reduced area, a cap slipped on said second area to abut said flange, a lock nut threaded to said body to clamp said flange and cap in position, an outwardly flaring end plate fixed to each said body and said cap, and resilient sealing members disposed between each plate and said flange.

6. A slush pump piston comprising a supporting body member having a radially extending flange intermediate its ends, a sheet metal end plate surrounding and attached to the body member adjacent each of the ends thereof, said plates a resilient sealing member abutting said plates and said flange.

being recurved radially inward toward said flange, andv a resilient sealing member abutting said plates and flange.

7. In a pump piston a supporting body member havlnga radially extending flange intermediate its ends, and foraminated sheet metal flanges secured to the opposite ends of said nonnn'r ALEXANDER Wilson. J

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